Time-indicating system



A. L. SOHM. TIME INDICATING SYSTEM. APPLICATION FILED FEB. 24, 1920.

1,394,647. Patented Oct. 25, 1921.

2 SHEETSSHEET 1.

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INVENTOR Add.

ATTOR NEY5.

A. L. SOHM.

TIME INDICATING SYSTEM. APPLICATION FILED FEB. 24, 1920.

1,394, 47, Patented Oct. 25, 1921.

2 SHEETS-SHEET 2. I

INVENTOR ATTORNEYS UNITED STATES ALFRED L. SOHM, OF CHICAGO, ILIIINOIS.

TIME-INDICATING SYSTEM.

Specification 01 Letters Patent.

Patented Oct. 25, 1921.

Application filed February 24, 1920. Serial No. 360,926.

T all w 7mm it may concern Be it known that I, ALFRED L. SOHM, a citizen of the United States, and a resident of Chicago, in the county of Cook, State of Illinois, have invented certain new and useful Improvements in- Time-Indicating Systems, of which the following is a specification.

My invention relates to time indicating systems and particularly to improved control by a master clock of an electrical secondary circuit and secondary units therein.

In time indicating systems to which my invention relates an electro-magnetically wound master clock controls the opening and closing of a circuit with which are connected the secondary units which are to be wound orset by means of electro-magnets. It is practically impossible to accurately and efliciently control a secondary unit circuit directly by contacts operated by the master clock mechanism. No matter how carefully the contact mechanisms are constructed double or false contacts are likely to occur and the more sensitive units in the secondary circuit may respond to such irregular con tacts and move forwardly, while less sensitive units would not respond, and the result would be non-synchronization and disorganization of the system.

One of theimportant objects of my invention is to indirectly control the secondary circuit through a relay, which relay is so constructed and so connected with the master clock and the secondary circuit that it will close the secondary circuit at the regular predetermined time intervals and keep it closed during critical periods when false circuit control might otherwise emanate from the master clock, the arrangement preventing the sending of more than one impulse through the secondary circuit for each time interval for which the master clock is adjusted.

The invention also covers improved contact mechanism, construction and arrangement in the master clock for controlling the operation of the relay.

The above and other features of my invention are incorporated in the structure and combination shown on the accompany ing drawings in which drawings- Figure 1 is a side elevational view of the master clock.

Pig. 2 is a front elevational view from plane 2--2, Fig. 1 and showing also the circuit connections between the master clock, relay, and secondary circuit.

Fig. 3 is a fragmentary rear elevational view to show the operation of the main spring winding mechanism, and

Figs. 4: to 8 inclusive show progressive positions of the master clock contact memers.

The supporting frame for the operating mechanisms of the master clock comprises the base 10, the front and rear plates 11 and 12 and the upper spacing members 13. Journaled in the front and rear plates is the minute arbor for supporting the minute hand 15, the hub 16 supporting the hour hand 17 being connected through a train of gears 18 with the minute arbor. On the arbor 14 is secured the gear 19 which mashes with the pinion 20 on the center arbor 21. 0n this arbor is secured the gear 22 which meshes with the pinion 23 on the escapement arbor 24 which carries the escapement wheel 25 engaged by t e escapement beam 26 supported on the upper arbor 27. A lug 28 extending rearwardly from the plate 12 supports the spring link 29 on which is hung the pendulum rod 30 carrying at its lower end the pendulum weight 30, the actuating rod 31 being secured to the arbor 27 and connecting at its lower end with the pendulum inthe well known manner.

Secured to the minute arbor 14: adjacent the gear 19 is the barrel 32 containing the main spring 33, one end of this spring being secured to the barrel and the other end being secured to the ratchet frame 34 rotatatable on the arbor adjacent the spring barrel. The ratchet frame (Fig. 3) has the ratchet teeth 35 engaged by the pawl 36 which is pivoted at its elbow on the plate 37, which plate is connected at its lower end with the armature 38 hinged at its front to the base 10. The vertical movement of the plate 37 is guided by means of the slot 39 which receives the grooved collar 40 secured to the minute arbor. A spring 41 connecting between the plate and the pawl tends to hold the pawl point against the ratchet wheel. Pivoted on the plate 12 above the ratchet wheel is the lock pawl 42 held by a spring against the ratchet wheel. A spring 44 connecting between the armature and the plate 12 tends to hold the armature up above the ends of the cores 45 and 46 of the electromagnet structure E, which cores project upwardly through the base plate 10. Whenlater.

winding 10 the armature 38 isattracted and swung downwardly and duringsuc'h'downward swing the lock pawl .42 holds theratchet wheel 34 while the plate 37 which moves downwardly with the armature carries the pawl 86 past a ratchet tooth so that when the armature is released and restored to the upper position the, ratchet wheel will be rotated and the main spring wound up correspondingly. V

The contact mechanism operated by the master clock comprises the contact wheel 47 and the contact levers 48 and 49 cooperating therewith to close circuits to bedescribed The contact wheel is secured on the arbor 21 and is therefore in electrical engagement with the frame-work of the clock. The wheel has eight contact points a to a inclusive. In the particular structure shown, this numberoi contact points together with the dimensions of the gearing train between the arbor 21 and the arbor 1 4 causes closure of the secondary unit cir cuit once every minute, as will be fully explained in detail later. [The contact lever 48 is secured on the arbor 50 journaled in the plates 11 and 12 to be thu'sadapted to swing in the plane'of the contact, wheel 47. Near its upper end the. lever carriesa contact plate 51 insulated therefrom and connected with the conductor 52 also carried by andinsulated from the lever. The weight extension 53 on the lever tends to swing it towardthe contact wheel.

7 The. stop post 54 limits-the outward swing of the'lever.

Adjacent the free'e'nd of the armature a kickoff lever 55 is pivoted intermediate its ends in the lugs 56 on the plate 10. The inner end of the lever extends below and in i the path of the armature whileits upstand ing outer end 57 is adjacent the arm 58c):- tending downwardly from the arbor 50 on The arran emcntis clearlv shown in Fig. 3'. When the armature is swung suddenly downwardly uponenern'ization of the ele tro-magnet, the

lever end 57 wi lstrike the arm 58 and the contact lever will he suddenly swung laterally awavfrom the contact wheel to disen gage andhold its contact 51 from the contact wheel teeth. V I 1 Above the contact wheel and pivoted ati'ts rio'htend of the front plate his the r latch pawl59Q this pawlnear its outer end,

and'in its under side havingthe outer'and nnerfabutment steps 60 and 61. These steps serve to receivejthe upper end of the contact lever 48. When this end isin eno ernent withthe inner step 61 the contact fplate 5 will be inthe path of the contact wheel teeth and when the lever is held outwardly by the outer step 60 the contact plate will be away from the path of the contact wheel teeth. The latch pawl has the pointed heel 62 in the path of the contact wheel teeth which serves a double purpose.

First it acts as an abutment whose engagement with the contact tooth will cause suifielectrical contact with the plate 51. Above the contact plate 51 theleverf48 has the overhanging portion 63 terminating in the sharp edge 64 just in advance of the contact plate, the purpose of the overhanging portion and edge being to clean a contact wheel tooth just before it reaches the plate, and

also to swing the lever 48 a distance outwardlyso that when the contact wheel tooth leaves the edge '64 the lever will be'thrownwith its contact plate against the contact tooth, thus further insuring good electrical contact. Each contact wheel tooth is thus cleaned twice before engaging with the contact lever and engagement of the. contact teeth with the heel 62 and overhanging part 63 also cleans these surfaces preparatory to their cleaning engagement with succeeding contact wheel teeth.

The contact lever 49 is pivoted on the arbor 65 extending between the plates 11 and 12 and the lever is adapted to swingin the plane ofthe contact wheel 47 its weight projection 66 tending to swing the lever toward the contact wheel. At its upper end it carries the contact plate 67 insulated therefrom and connected with the conductor 68 carried by and insulated from the lever. A stop pin 69 limits the outward, swing of the lever beyond the influence of its weight. pro ectm'n; 66. The pin 70 limits the inward swing'ofthe lever. Justin advance of the contact plate 67 the lever has secured on its frontedge the cleaning lug 0r guard '71 along whi h the contactlwheel teeth travel to be cleaned before being engaged by the contact plate 67 as the lever is swung in- Y wardly when the the tooth. c

'Reterring to F ig- 2, Rrepresents a relay interposed between the master clock and the secondary circuit 8' with which are connected the various secondary unitsfs. The relay is shown diagrammatically but its detai-led construction-is disclosed in my Patent guard lug is released from No. 1.302604 dated May 6th,,1919. Briefly des'ribing the relay it comprises the circuit closing electro-magnet' '72 having, the. wind{ ing 7 3, andthe unlocking electro-magnet 74 having the winding 75. The electro-magnet 72hasthe armature 76 adapted when at-' tracted to engage with the contact 77. The

armature 78 for the electro-Inagnet 74 has the latch arm 79 terminating in the latch end 80, a spring 81 tending to swing the armature 78 to hold the latch end in the path of the armature 76 so that when its armature is attracted it will glide past the latch end and be locked thereby in engagement with its contact '37 until the electro-magnet 7 1 is energized ant its armature attracted to raise the latch.

The master clock has the shelf 82 extending therefrom for supporting the terminal posts 83, at and 85 and the terminal post 86, the last mentioned post being in electrical connection with theframe-work of the master clock and thereby always in electrical engagement with the contact wheel 17, while the other three terminal posts are insulated from the frame-work. The post 83 is connected through conductor 87 with the conductor 52 leading to the. contact plate 51. The contact post 84 is connected by conductor S8 with the conductor 68 leading to the contact plate 67 of lever 49. The electroagnet windings w are connected in series and their free terminals connect respectively with the binding posts 85 and 86. The binding post 83 is connected by conductor 89 with one terminal of the winding 73, the ot er terminal of which connects with the contact 77 and with one pole of the battery B. The other pole'of the battery connects with the limb 90 of the secondary circuit whose other limb 91 connects with the armature 76. The binding post 84; is connected by conductor 92 with one terminal of the winding whose other terminal is connected by conductor 93 with the limb 91 of the secondary circuit. The binding posts 85 and 86 are connected by conductors 94; and 95 respectively with the limbs 91 and 90 of the secondary circuit so that the electro magnet windings w are in bridge of such circuit.

Figs. 4 to 8 clearly show the cycle of operation. The contact wheel rotates in the direction indicated by the arrow thereon. In Fig. 4 the contact tooth a is traveling toward the contact plate 51, the detent pawl 59 holding the lever 48 out by its outer step 60. Thecontact tooth a is just about to engage with the heel of the latch pawl and the tooth 0. is approaching the lug 71 on the lever 19. Both electro-magnets of the relay 1% are deener ized and the armature 76 is in its open. circuit position as indicated by dotted lines Fig. 2. As the contact wheel rotates, the tooth a will engage with the heel 62 of the latch pawl to raise the pawl sutiiciently to permitthe lever 48 to swing into engagement with the inner step 61 to thereby carry its contact plate 51 into the path of the 011-001111ng tooth 0. The tooth a? is just coming into en agement with the lug 71 on lever 49, all as shown in Fig. The next position of the parts is shown in Figs. 2, 4 and 6. The tooth a has left the latch pawl to leave it free to rest on the lever 18, and the tooth a has just wiped across the overhang portion 63 and its point (3stand is in engagement with the contact plate 51. The tooth (i is at the end of the lug 1. As soon as the tooth a contacts with the plate 51 circuit is closed through the winding 73 of the relay electro-magnet 72, the circuit being traced as follows: battery B, winding 73, conductor 89, post 83, conductor 87, conductor 52 and contact plate 51, contact wheel 47, clock frame and post 86, and conductor 95. Upon closure of this circuit the armature 76 is attracted into engagement with the contact 77 to close the secondary circuit S which will then be supplied with current from the battery B, and all the secondary units 8 and also the electromagnet E of the master clock will be energized. Immediately upon energization of the master clock electro-magnet, its armature is drawn down and the kick lever 55 is struck thereby and rotated to engage the arm 58 on the arbor 59 so that the contact lever 18 is swung away from the contact wheel, as indicated in dotted lines Fig. 6. lhe lever weight 58 then swings the lever inwardly but the lock pawl is in the way and its step 69 receives the lever to hold its contact plate out of the path of the contact wheel teeth, as indicated in Fig. 7 Swinging away of the contact lever from the contact wheel will of course open the circuit just traced through the electroanagnet winding 72-, but immediately when the armature of this electro-magnet was drawn up the latch end received it and locked it against its contact 77 so that closure of the secondary circuit is maintained. After opening of the circuit by swinging away of the contact lever the contact wheel tooth a still has some distance to travel along the lug 71 and this gives the contact lever a chance to become firmly established in its position in engagement with the outer step of the detent pawl. Even though the contact lever should miss the pawl or be jarred loose, and engage with the contact wheel during engagement of the too-3h a with the lug 71, it could not cause false impulse through the secondary circuit on account of the locking of the circuit in closed condition by the latched armature 76.

After the contact tooth 0. leaves the lug 7 the contact plate 67 will be carried a ainst the tooth by the lever 49 and circuit will be closed through the winding 75 of the relay electro-magnet 7%, this circuit including the armature 76 and its contact 77. The circuit is traced as follows: battery B, contact 77, armature 76, conductor 93, winding 75, conductor 92, post 84, conductors 88 and 68, contact plate 6'7, contact wheel 47, clock frame and post 86, and conductor 95. Jpon energization of the electro-magnet 74 its armature 78 is attracted and the lock lever 79 raised to release the armature 76 so that the secondary circuit is opened. The contact engagement between the tooth and the contact plate 6'? is of suflicient duration to give the unlocking electromagnet ample time to perform its unlocking work. lVhen the tooth leaves the contact plate the electro-magnet 74 is deenergized and its armature released to permit the latch point 80 to again position itself in front of the retracted armature 76 ready for the next locking operation. After engagement of the tooth a with the con tact lever 48 and engagement of the tooth a with the contact lever 49, the next too-ch a will cooperate with contact lever 48 and the tooth a with the lever 49, and the cycle of operations will be repeated. 7,

96 represents a non-inductive resistance connected with the binding posts 85 and 86 to be in bridge of the electromagnet windings w. 'lhis resistance will take care of the counter-current generated when the electro-magnet circuit is broken.

My improved construction, arrangement and operation is very substantial and eihcient. Thesecondary circuit which controls the synchronization of time at the various units and thewinding thereof is kept closed during the critical period when irregular and false current impulses would tend to occur. Disorganizationrof a time indicat ing system is therefore fully guarded against. 7 7

Having described my invention, I claim as follows: I 1.' In a time indicating system, the combination of a master clock comprising a clock train, a'contact wheel connected to be driven by said train, an electro-magnet ttSSOCIEIlZBCl with said clock, a secondary circuit with whichsaid electro magnet is connected, a main contact lever associated with said contact wheel, means controlled upon engagement of said lever with said wheel forclosing said secondary circuit, locking means controlled upon first closure of said circuit forlocking said circuit closed independently'of said lever and wheel, said Z magnet beingadapted upon closure of such circuit to release said lever from said wheel to thereby open the circuit at such point, a second contact lever associated with said contact wheel felectro-magnetic unlocking nieans and a circuit therefor, engagement of said second contact lever with said contact wheel causing closure of said unlo king means circuit and actuation of said unlocklllggIliBilIlSftO open, sald secondary circuit. 7 Quln a time indicatingsystem, the comfblIlEttlOIl of a master clock, a contact wheel drivenby the clock tram, an electro-magnet associated with said clock, a secondary circult with which said electro-magnet is con- 7 and connected'with aid secondary circuit,

energlzation of said electro-magnet causing nected, a contact lever associated with said contact wheel, a relay, a circuit for said relay closed upon engagement of said contact lever with said contact wheel, contacts controlled upon energization of said relay for closing said secondary circuit, means for locking said contacts togetherto maintain closure of said secondary circuit, means whereby energization of said electro-magnet upon closureof said secondary'circuit will cause disengagement of said contact lever and contact wheel whereby to open said circuit, a second contact lever associated with said contact wheel, an unlocking electro-magnet and a circuit for said unlocking electro-magnet closed upon engagement of said second contact lever with said contact wheel, said unlocking electro-magnet actuating said locking means'to' cause un-' locking of said contacts and reopenlng of with said secondary circuit to be energized upon closure thereof, means actuated upon energization of said electro-magnet for releasing saidcontact lever from said contact wheel to open the relay circuit at said point, locking means for locking the relay contacts to keep the secondary circuit closed immediately after, first closure of said. relay circuit, electro-magnetic unlocking means, a circuit for said unlocking means, and a sec-' ond contact lever associated with said contact wheel to close said unlocking means, circuit to cause actuation thereof to control the locking means to unlock said relay contacts and thereby reopening of the secondary circuit.

4. In a time indicating system, the combination'of a master clock,'a contact wheel driven by the clock train, a contact lever adapted "to periodically engage 'with said contact wheel, a relay, a circuit forsaid relay controlled by said contact 'lever and 7 Wheel," a secondary circuit closed by saidrelay when the relay'circuit is first closed, means for locking said relay to maintain clo-i sure of said secondary circuit independently of said contact lever andwheel, an electromagnet associated with said contact lever release of said contactlever fromsaid wheel. toopen the relay circuit at that point im' mediately after closure of said circuit, a sec-.

0nd contact lever associated with. said contact "wheel, an unlocking electro-magnet for unlocking said relay topermit reopening of the secondary circuit, and a circuit for said unlocking electro-magnet controlled by said contact wheel and second contact lever, said circuit including the relay contacts.

5. In a time indicating system, the combination of a master clock, a contact wheel driven by the clock train, a contact lever associated with said contact Wheel and adapted to periodically engage therewith, a relay, a circuit for said relay closed upon engagement of the contact lever with said wheel, contacts for said relay closed upon energization thereof, a secondary circuit connected with said contacts, an electro-magnet connected with the secondary circuit and adapted upon energization to Withdraw said contact lever from the contact wheel to open the relay circuit at that point, locking means for locking the relay contacts immediately upon first closure of said relay circuit whereby to maintain closure of the secondary circuit independently of said contact lever and wheel, a second contact lever associated with said contact wheel, an unlocking electro-magnet for unlocking said relay contact to permit reopening of the secondary circuit, an energizing circuit for said unlocking electromagnet, said second contact lever and wheel cooperating to close the circuit for the unlocking electro-magnet after a period of closure of the secondary circuit by the locked relay contacts.

6. In a time indicating system, the combination of a master clock, a relay, an energizing circuit for said relay, contact mechanism controlled by the clock train to periodically close said relay circuits, a secondary circuit closed by said relay upon energization thereof, means for locking said secondary circuit closed independently of said clock contact mechanism, an unlocking electro-magnet associated with said relay, a circuit for said unlocking electro-magnet including the rel ay contacts, and additional contact mechanism controlled by the clock train to close said unlocking circuit after a period of closure of the secondary circuit by said relay, energization of said unlocking electro-magnet causing unlocking of the relay and reopening of the secondary circuit.

In witness whereof, I hereunto subscribe my name this 19th day of February, A. D.

ALFRED L. SOHM. 

